The present invention refers to automotive air blowers and, in particular to automotive superchargers, which are devices which may be incorporated in automotive engines. Superchargers are devices that include an air pump or blower wheel, rotation of which changes the pressure conditions in the inlet system of the engine, the inlet pressure. Commonly the device is configured and operated in a way that increases the inlet pressure and therefore enables the power output of the engine to be increased. Alternatively the device may be configured to lower the Inlet Pressure and reduce the power output, this method of power control offering efficiency advantages when compared with the conventional method of load control through a throttle valve.
An air blower in accordance with the invention may, however, also take other forms, such as an automotive cooling fan for blowing air over a cooling radiator.